Urbanized areas are becoming increasingly warm during night, a time most places experience a cool-down. According to climatologists, the more development there is in an urban area, the more heat it retains throughout the day -- and night.
The heat wave spreading across the United States has been felt even more in the country's urbanized areas, a trend known as the heat island effect. Nighttime low temperatures are breaking records left and right as the built urban environment absorbs the heat of the day and holds it throughout the night. In Southern California, nighttime lows have steadily increased in recent years, reaching record temperatures between 77 and 100 during nights this summer.
"Climatologists say global warming gets some of the blame. But the prime villain, they say, is the ever-increasing urbanization of the region. The rapid development of Southern California over the last 50 years has created structures and landscapes that retain heat better than dry desert chaparral."
"Golf courses, shopping centers, housing developments and lush lawns trap heat during the day, keeping temperatures up at night."
FULL STORY: High Nighttime Temperatures Set Records Too

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